1. Technical Field of the Invention
The present invention relates to light generating instruments for curing light-curable compounds, such as those utilized in dental applications. More particularly, the present invention relates to curing fight instruments having an integral compressed-air delivery system, which is used to dry the treatment area and spread the adhesive compounds.
2. Description of the Related Art
Light-curable compounds, such as adhesives and bonding or filling compounds, are widely used in dental applications to attach objects to surfaces or to fill gaps or other openings, such as a cavity, in a tooth. Such curable compounds are generally available in a semi-solid state, and are manipulated and positioned on the surface or in the gap as desired, and hardened or cured into a more solid state for permanency. Curing or hardening is generally a chemical polymerization process which is promoted and driven by various curing conditions and factors. For example, a semi-solid compound or component thereof, may be cured by exposure to air or to energy, such as heat or light energy.
Today, many adhesive and filling compounds are cured by exposure to light energy, particularly visible light energy. The light curing process involves directing a beam of light, such as visible light, at a specific wavelength or band of wavelengths onto a semi-solid light-curable compound to cure the compound. The compound includes light sensitive, chemical components therein which, when exposed to light at the specific wavelength, generally polymerize to harden the compound onto the work surface to bond, fill, or coat the surface.
Specifically, light-curable compounds are widely used in dental procedures. Dentists use light-curable compounds for tooth repairs in a variety of applications including a base, a liner, a coating, a surface seal, a filling for caries and cavities, and to secure crowns or similar dental structures to a tooth surface. Generally, visible light in the blue range of the light spectrum will be sufficient to cure most commonly used dental compounds. Once cured, the dental compound functions, for example, to reduce further tooth decay, to bond dental structures, and/or to provide additional structural support to a tooth.
Generally, curing is effected by various instruments or devices capable of generating visible light and directing this light onto a tooth surface containing the light-curable compound. The light penetrates into the compound layer on the tooth surface for complete curing. The duration of the exposure to light for proper curing of the compound layer depends upon the light-curable compound itself, thickness of the compound layer, and the power and characteristics of the blue light emitted from the curing light instrument. For example, curing a compound to provide a thin tooth surface coating or veneer will require less light energy, while curing a compound to provide a thicker, deeper filling for gaps, such as caries and cavities, will require a greater amount of light energy.
A variety of proposals have previously been made to improve dental curing light devices, which deliver visible light to the tooth. For example, U.S. Pat. No. 7,182,597 to Gill et al. discloses a small, hand-held, sell-contained curing light instrument, which efficiently and effectively cures light-curable compounds by maximizing the amount of light directed onto the light-curable compound. The Gill et al. '597 device comprises a hand-held curing light instrument, which includes battery-powered light emitting device and a light guide projecting from a distal end that transmits and directs the generated light to the treatment area. The instrument further includes an electronic control circuit, which controls the time the radiation generated by the light emitting device is emitted, and may further control other factors related to the emission of curing light. The light emitting device emits the light necessary to cure the light-curable compound.
While prior art proposals have greatly advanced the efficiency and effectiveness of curing light instruments, they continue to exhibit a number of drawbacks. Presently, the completion of any dental procedure involving a light-curable compound typically requires a dentist to first use an air-water syringe attached to the chair side dental delivery system to dry the treatment area. After drying the treatment area, the air-water syringe is placed back in the chair side delivery system. The dentist then applies an adhesive layer. Next, the dentist again picks up the air-water syringe to spread and shape the adhesive layer with compressed air. The air-water syringe is again placed back in the chair side delivery system and the Curing light is picked tip, turned on, and the light is applied to the treatment area to cure the light-curable adhesive compound.
The use of such dental delivery systems is inherently problematic with regard to dental procedures involving light-curable compounds. The use of light-curable compounds in dental applications requires a dry and clean operating environment and treatment area. Any water or oil contaminants introduced into the treatment area will reduce the bond strength and increase the risk for failure of the restoration. Dental delivery systems typically operate with the use of an engine driven compressor. Air and water are delivered to the chair through the same tubing. Thus, the probability of oil from the compressor or residual water in the lines reaching the proposed treatment area is high. These contaminants can cause bond failure.
Thus, there is a need to provide an improved curing light instrument to cure compounds in a faster, more efficient, and effective manner. Accordingly, it is desirable to provide a curing light instrument having an integral, self-contained compressed-air system, which allows the dentist to complete a dental procedure involving the use of light-curable compounds using a single hand-held instrument.
It is also desirable to provide a curing light instrument, which provides a controlled blast of clean, dry air, and eliminates the possibility of contamination of oil and water into the bonding environment of the treatment area.
It is further desirable to provide an improved curing light instrument having an integral, self-contained compressed-air system, which further includes an inter-changeable light guides incorporating a variety of air nozzle configurations, which supply controlled blasts of clean, dry air to the treatment area.